Combined automatic shutter-opening and gravity valve-lifting mechanism for furnace oxidators



N6 MEcgANIsu Nov. 9 1926.

J. J. A. MILLER OPENING AND GRAVITY VALVE LIFTI 2 Sheets-Sheet 1 COMBINED AUTOMATIC SHUTTER FOR Original FURNACE OXIDATGRS Filed March 13 1923 A. MILLER- ING 'J; PEN

a MBCHANI su COMBINED AUTOMATIC SHUTTER 0 AND GRAVITY VAjJVE LIFTIN FOR FURNACE OXIDATORS Original F 2 Sheets-Sheet 2 iled March 13, 1,923

v f7welator:

IN l S I l A- U HEE EE T a K W r Patented Nov. 9, 192$.

wires statues r FEW JOHN J. A MILLER, OF BENVER, COLORADO.

COMBINED AUTOMATIC My invention relates Application filed March 13, 1923, Serial EN QFFlCE.

SHUTTER-GPENING AND GRAVITY VALVE-LIFTING MEGHA- NESM FOB. FURNACE OXIDATOES.

to improvements in a combined automatic shutter-opening and gravity valve oxidators.

The ob ect of lifting mechanism for furnace the invention is to provide,

in connection with a furnace oxidator comprising an air pr the furnace door cheater which is secured to shutters for admitting air through said preheater, and an oil-controlled gravity va a predetermined time after ed mechanism nd lifting closing of the furan improv opening said shutters, a

simultaneously with the nace door, said mechanism being secured upon the door.

Further, to provide in connection with a series of connected shutters, ed to one of said shutters trolled gravity ing of said s opened of mechanism s opening said shutters,

controlled pivoted arm, nected thereto and opera the door to swing said arm, said shaft which is eng lve for-closing said shutters within the door is closed; for automatically said valve,

a shaft connectand an Oll convalve which is lifted by turnhaft when the shutters are ecured to the door, for

comprising a spring a plunger bolt c0mted by the closing of and a tappet on a ed by said arm mechanism ill These objects drawings, in which Fig. 1 is a f equipped with trolled gravity ters, and the impr ing said shutters valve Fig. 2 er port nected ing closed;

Fig. showing the do shutter ope 3 is a view simi or in section, the parts rating mechanism being in the rent view of a air inlet shutters, an oil convalve for closing said shutoved mechanism for openand lifting said gravity thereto, shown in Fig.

its normal positlon,

are accomplished by the ustrated in the accompanying furnace door is an enlarged edge view of the lowion of the furnace door and parts con- 1, the door belar to Fig. 2, but

of the positions they assume when the door is open;

Fig i is a hor line t-l of Fig. 1. a port tor being hown:

izontal sectional view on the ion only of the pre- 1T0, 624,858. Renewed March 31,

Fig. 5 is a horizontal sectional view, similar to Fig. 4 but on a smaller scale, and showing the complete preheater;

Fig. 6 is a vertical size-of the oil controlled its housing;

Fig. 7 is a rear view of the sectional viewfull gravity valve and preheater and Fig. 8 is a vertical sectional view through the shutter supporting frame and its shutters, three shuttters being sh four, as in Fig. 1.

The device as whole, as illustrated in the own instead of accompanying drawings, constitutes a smoke abating appliance or oxidator, for attachment to furnace doors, and embodies a combined shutter opening and valve lifting mechanism which is an improvement over mechanism for accomplishing the same operation,

which is shown in pending application filed by me onthe 9th day of October, 1922, for automatically operating oxidators for attachment to furnace doors for abating smoke, Serial No. 593,475, and for automatically operating shutter openi mechamsm for furnace oXida 593,474, and also for auto and closing Serial No. matically conng tors,

trolled smoke abating oxidators for attachment to furnace doors, filed August 1, 1922,

Serial No. 579,050.

Visible furnace smoke can be abated only y floating particles of carbon each coaling operation, and plished only effecting complete combustion of the and tar after this IS accomby supplying air suflicient for the complete oxidation of all combustible matter and the intimate mixing of the air with the combustible gases and the floating particles of tar and carbon;

to bring about this result, air in large quantities should be admitted over the coaling and this quantity sh ally reduced, as the distillati fire immediately after ould be graduon of the volatile combustible nears completion.

The improved furnace door attachment is adapted to meet these requirements by means of a combinationof elements, which are arranged and constructed as follows Referring to the accompanying drawings, the numeral 1 indicates the front wall of a furnace, 2 the coal opening therein which is surrounded by a marginal lip 3, and t the fire door which is hinged to the said wall 111 the usual manner and is provi able handle 5.

ded with a suit- The door is provided with an opening 6 of suitable size and to the outside of the door, and surrounding the opening 6 is secured arectangular frame 7, having apertured lugs 8 through which bolts 9 are passed and which also pass through the door.

An air heater is secured to the rear side of the door to register with the opening therein, and this heater comprises a rectangular metal frame 10 having outwardly flaring sides, the smaller end of the frame being provided with integral, bolt-receiving lug; 11 which are secured to the door by bolts 12, the door-engaging faces of the said lugs 11 being extended beyond the adjacent end of the frame in order to leave a space 13 between the door and this end of the frame. The opposite end ofthe frame is curved On an arc whose center is the axis of the hinge pin of the said door, the radius of said are being such as to permit the heater frame 10 to swing througi the coal opening 2 when the door is opened, without contacting with the marginal edge of said opening, as will be understood by reference to Fig. 5. Spaced vertical blades or plates 14.- extend from the inner straight edge of the frame, to its curved outer edge, and these blades are connected by a central horizontal plate 15, the whole heater being in the form of an integral structure. By constructing the heater in this manner, a maximum heat ing surface is provided, and when the door is closed, the heater projects into the combustion chamber and over the coal bed and is thus heated to a high temperature, so that atmospheric air passing through the said heater, will also be heated to a high temperature before passing over the coal bed, as will hereinafter fully appear.

A series of overlapping dampers or shutters 16 are pivotally mounted in' the frame 7 by screws 17' which are passed through threaded holes in the sides of the said frame, but which are provided with unthreaded end portions which enter apertured lugs 18 which are formed centrally on the ends of the shutters. The shutters are in the form of thin metal blades and they are connected to turn in unison by a bar 19 which lies between and is pivotally connected to pairs of lugs or ears 20 which are fomed on the shutters adjoining their lower edges. Any preferred number of these shutters may be employed.

The lug 18 is omitted from one end of one of the shutter: and the bifurcated end of a shaft 2i is placed over this end of the shutter and is secured thereto by a screw or rivet. The shaft 21 passes through the adjacent side of the frame 7 and also through two opposite sides of a rectangular housing 22 which is bolted to this side of the frame, the side of the housing farthest from the frame being formed with an apertured boss or. hub 23 through which the said shaft passes and which forms a bearing for the same. The free end of the shaft extends beyond this bearing hub and has pivotally mounted thereon a tappet 24, the upper or pivoted end of which is bifurcated. The front edge of this tappet is parallel with the rear edge for substantially half its length and is at an angle to the said rear edge for the rest tappet being wedge shaped, as clearly shown in Figures 2 and 3. A pin 25 is rigidly secured in the projecting end of the shaft 21 and projects forward from the same at a downward inclination of forty-live degrees. This pin passes through the bifurcation in the tappet and the bottom of the bifurcation abuts against the pin, and the pin thereby holds the tappet at a rearward inclination of forty-live degrees, or at right angles to the axis of the pin, the under or be\ eled portion of the tappet being at a slight angle to a horizontal plane.

reference to Fig. 2, it will be seen that a forward swinging movement of the tappet will result in a partial rotation of the shaft 21, and this forward swinging movement is accomplished in the following manner 1- A bracket 26 is bolted to the furnace door adjacent its lower edge and in vertical line with the tappet 24. This bracket extends for about half itslength below the lower edge of the door and comprises a flat plate which is centrally bifurcated from its upper edge for about half its length, and is formed with parallel integral ribs 27 which extend the length of the plate and project at right angles thereto, and which are spaced for a portion of their length to coincide with the width of the bifurcation in the plate, as shown at 28, and for the remainder of their length the space between them is more contracted, shown at 29. The lower end of an arm 30 is inserted in the contracted space 29, and is pivotally mounted upon a pin 31 which pa'ses through the ribs and through the lower end portion of the arm. A plunger pin 32, having a bifurcated end is passed through a hole in the door, which registers with the lower end portion of the bifuration 28 of the bracket 26, and the bifurcated end of this pin ispivotally connected to the arm 30, and when the door is closed the free end of the pin engages the lip surrounding the door opening, and the pin is thereby projected forward, thus swinging the arm 30 outward on its pivot 31. The are through which the upper end of the arm pastes intersects the are through which the end of the tappet 24 passes and thus the tappet is engaged and swung forward by the upper end of the arm. The lower edge of the bracket 26 is formed with lugs 34, adjoining the ribs 27, the front edges of which are notched, and into these notches of its length, the lower half of the i lie the lower end portions of parallel members of a yoke shaped spring 35, the upper closed end of which lies in a notch 36 in the front edge of the arm midway between the plunger pin 32 and the upper end of the said arm. Each arm of the spring 35 is formed with a coil 37, and the lower extremities of the arms terminate in right angled bent portions 38, which extend under the lugs 3a and prevent upward movement of the spring, while the notch 36 in the edge of the arm 30 prevents downward movement of the spring. The spring 35 acts to swing the arm 30 rearward or toward the door when the said door is opened, as will fully hereinafter appear.

A cylinder 39 depends from the bottom or the housing 22, which is adapted to be filled with a suitable oil. A hollow piston 40 is mounted in this cylinder, the bottom end ct which is provided with an axial aperture 41, while its upper end comprises an upwardly projecting axial hub 42 which is connected by spokes 3 with the upper edge portion of the piston. The reduced portion of a piston rod 44 is inserted in the hub l2 and is held therein by a pin 45, which passes through the hub and through a groove in the said reduced portion. The piston rod is in the form of a rack bar having annular teeth l6 and is provided with an axial hole l? which extends entirely through the same, the lower portion of this hole being threaded. A stem as is screwed into the threaded portion of the hole and extends through the hole 41 in the bottom of the piston The portion of the stem projecting through the bottom of the piston is reduced in diameter, as shown at d9, to form a shoulder at the junction of the two diameters, and a disk valve 51 having an axial hole, is slipped on the reduced portion and is normally held against the shoulder 50 by a spiral coil spring which surrounds the reduced portion of the stem and is held in place by a pin which passes through the reduced portion and engages the lower coil of the spring. 1

he housing 22 is closed by a cap 54, hav ing a threaded hole 55 in line with the axial hole 47 in the piston rod, which is normally closed by a screw 56. The upper end of the stem 48 is provided with a screw driver slot, and by passing a screw driver down through the hole 55 in the cap and into the hole 4:? in the piston red, the valve stem may be adjusted to vary the distance between the disk valve El and the bottom end of the piston, by which the period required for the piston to make its QlOWllu'fl'iCl stroke through the oil. in t1 e cylinder may be lengthened or shortened to meet requirements, for a reason to be hereinafter forth, and the spring,

52 pern'iits the valve to move downward away from the hole a1, under the pressure plunger pin of the oil when the valve is raised, so as to permit lree passage of the oil through the piston.

The portion of the shaft 21 which passes through the housing 22 has rigidly mounted thereon a segment gear 57 which meshes with the toothed piston rod 4A.

The bottom of the piston is slightly concaved, as shown in Fig. 6 and is provided with a drain hole which is normally closed by a'screw 58, by removing which, the oil in the cylinder may be drawn oil when desired.

In operation, the cylinder is filled with suitable oil, and the disk valve 51 is adjusted to control the flow of oil through the piston, so that the piston will descend to the limit of its downward stroke, within a given period. Assuming that the piston is down to the limit of its stroke, the shutters 16 will then be closed, thus preventing air from entering thefurnace through the preheater. When it is necessary to stoke the furnace, the door t is swung open, and the 32, which was projected to the limit of its forward movement, by the engagement oi its free end with the lip 3 of the door opening, is thrown to the limit of its rearward movement by the spring 35, the upper end of which bears against the outer edge of the arm 30, to which the plunger pin is pivotally attached. As the arm 30 is thus swung rearward to the position shown in dotted lines in Fig. 2 and in full lines in Fig. 3, its upper end engages and swings the tappet 2 L upward until it clears the tappet, which then drops back to its normal position. The parts remain in the positions shown in Fig. 3 until the door is again closed, when the free end of the plunger pin 32 engages the lip 2-3, whereby the pin is thrown forward, and the arm 30 is thereby also swung forward to the position shown in Fig, 2. In describing this outward swinging movement, the upper end of the arm engages the tappet 24 and swings the same forward, and this movement or the tappet turns the shaft 21 a fourth of a complete rotation by reason oi? the engagement of the closed end of the bifurcation in the said tappet, with the pin 25 which is secured in the said shaft. This quarter rotation of the shaft swings the shutters l6 open'to horizon tal positions and also imparts a quarter rotation to the segment 57, by which the piston 40 is raised from its lowest to its highest position. As the upper end of the arm passes clear of the end of the tappet, the tappet drops by gravity to a vertical position and the piston immeciately begins to descend and the shutters begin to close, and during the closing period of the shutters, which depends upon the length of time required by the piston to descend to its lowest position, air in a continuously decreasing volume is admitted to the combustion chamber through the preheater, with the results hereinbefore described. As the shaft 21 turns on its reverse movement, the pin 25 again engages the closed end of the bifurcation in the tappet and swings the same to the position shown in full lines in Figures; 1 and 2. When the tappet is manually swung to the position shown in dotted lines, 2, it is out of the path of travel of the end of the arm 30, and the door may then be opened without turning the shaft 21, and therefore without opening the shutters or lifting the piston.

Having described my invention, what i claim as new and desire to secure by Letters Patent is 1. In a device of the character described, the combination with a furnace door having a preheater thereon, connected shutters for admitting air to the furnace through said preheater, and a shaft connected to one of said shutters; of a tappet loosely mounted on said shaft, but adapted to turn the shaft when swung in one direction, means on the door and actuated by the closing of the door for moving said tappet in its shaftturning direction whereby said shutters are opened, and a gravity device connected with said shaft and lifted thereby sil'nultaneously with the opening of the shutters, for c105:- ing said shutters within a predetermined period.

2. In a device of the character described, the combination with a furnace door having a preheater thereon, connected shutters for admitting air to the furnace through said preheater and a shaft connected to one of said shutters; of a tappet loosely mounted on said shaft, a stop on said shaft which is engaged by the tappet when said tappet is moved in one direction, thereby to turn said shaft and open said shutters, means on the door and actuated by the closing of the door for swinging said tappet in its shaft-turning direction through a predetermined arc and then releasing the same, and a gravity device connected with said shaft and lifted thereby simultaneously with the opening of the shutters, for closing said shutters within a predetermined period.

3. In a device of the character described, the combination with a furnace door having a preheater thereon, connected shutters for admitting air to said furnace through said preheater and a shaft connected to one of said shutters; of a tappet loosely mounted on said shaft, a stop pin on said shaft which is normally engaged by the tappet, an arm piv otally mounted on the door and a plunger connected'to' said arm and actuated by the closing of the door, wherebysaid arm is caused to engage and swing said tappet against said stop pin through a predetermined arc and then clear the same thereby to turn said shaft and open said shutters, and a gravity device connected with said shaft and lifted thereby simultaneously with the opening of the shutters, for gradually closing said shutters within a predetermined period.

4:. The combination with a furnace door having a preheater thereon, connected shutters for admitting air to said furnace through said preheater and a shaft connected to one of said shutters; of a tappet loosely mounted on said shaft, a pin projecting from said shaft which is normally engaged by said tappet, an arm pivoted to said door, a plunger pin pivoted to said arm and extending through said door and adapted to be projected by engagement with the front wall of the furnace when the door closed, whereby the said arm is caused to engage and swing said tappet outward against said stop pin through a predetermined are and then clear the same thereby to turn said shaft and open said shutters, and a gravity valve connected with said shaft and fitted thereby simultaneously with the opening of the shutters, for gradually closing said shutters within a pre determined period.

5. The combination with a furnace door having a preheater thereon, connected shut ters for admittin air to the furnace through said preheater and a shaft connected to one of said shutters having a projecting pin; of a tappet loosely mounted on said shaft in normal engagement with said pin and adapted when swung in 'one direction to turn said shaft and open said shutters. an arm pivoted to said door the upper end of which is adapted to move in an arc which intersects the arc described by the end of said tappet, a plunger pin pivotally connected to the arm and extending through said door and adapted to be projected by ongagement with the front wall of the fur nace when the door is closed, whereby the upper end of said arm engages and moves said tappet in its shaft-turning direction through a predetermined are and then clears the same, a spring for reversing the movement of the arm when the door is opened, and a gravity oil-controlled valve connected with said shaft and lifted thereby simultaneously with the opening of the shutters for gradually closing said shutters within a predetermined period.

6. In a device of the character described, the combination with a furnace door having a preheater thereon, connected shutters for admitting air to the furnace through said preheater and a shaft connected to one of said shutters and provided with a projection; of a tappet loosely mounted on said shaft in normal engagement with said projection and adapted to turn the shaft when swung in one direction, a bracket on said door, spring controlled arm pivoted to said bracket the upper end of which moves in an are which intersects the are described by the end of said tappet, a plunger pin connected to said arm and extended through said bracket and said door and adapted to be projected by engagement with the front of the furnace when the door is closed, whereby the arm is swung and the tappct thereby actuated to turn the shaft and open the shutters, and an oil controlled gravity device connected with said shaft and lifted thereby simultaneously with the opening of the shutters, for gradually closing said snut lQi'S within a predetermined period.

7. The combination with a furnace door having connected air inlet shutters thereon and a shaft connected to one of said shutters, having a tappet loosely mounted thereon and adapted to turn the shaft when swung in one direction; of an arm pivotally mounted on the door and adapted to be swung by the closing of the door to swing said tappet'in sha t-turning direction and thereby ope-n said shutters, and gravity means connected with said shaft and lifted thereby simultaneously with the opening of the shutters, to gradually close said shutters within a predetermined period.

8. The combination with a furnace door having connected shutters thereon, a shaft connected to one of said shutters having a projecting pin and a tappet loosely mounted on said shaft, its mounted end being bifurcated to receive said pin and engage the same to turn the shaft when swung in one direction, of a spring controlled arm pivotally mounted on the door, the upper end of which moves in an are which intersects the are de scribed by the free end of the tappet, a plunger connected to said arm and extended through said door and adapted to be projected by engagement with the front wall of the furnace when the door is closed whereby the arm is swung and the tappet actuated to turn the shaft and open the shutters, and gravity means connected with the shaft and lifted thereby simultaneously with the open ing of the shutters for gradually closing said shutters within a predetermined period.

9. The combination with a furnace door having a series of connected air inlet shutters thereon, a shaft connected to one of said shutters and a tappet loosely mounted on said shaft and adapted to turn the same when swung in one direction; of a bracket on said door, an arm pivoted at its lower end to said bracket, its upper end being adapted to move in an are which intersects the are traveled by the free end of the tappet, a plunger bolt pivoted to said arm at one end, and above the pivot of said arm, said bolt extending through said bracket and said door and adapted to be projected by engagement with the front wall of the furnace when the door is closed, whereby the arm is swung outwardly and the tappet is engaged by the upper end of said arm and thereby actuated to turn the shaft and open the shutters, a spring on said bracket for swinging said arm rearward when the door is opened, its upper end swinging said tappet in a reverse direction and clearing the same and an oil controlled gravity piston connected with said shaft and lifted thereby simultaneously with the opening of the shutters, for gradually closing the same within a pre determined period.

10. The combination with a furnace door having connected air inlet shutters thereon, a shaft connected to one of said shutters and a tappet loosely mounted on said shaft and adapted to turn independently of the shaft when swung in one direction, but to turn the same when swung in the opposite direction; of a slide bolt extending through said door and adapted to be projected by engagement with the furnace front when the door is closed, a spring-controlled arm connected to and operated by said bolt and adapted to swing said tappet and thereby turn said shaft and open said shutter, an oil controlled gravity piston on said door, and means connected to the shaft for lifting said piston simultaneously with the opening of the shut ters for gradually closing the same within a predetermined period.

11. The combination with a furnace door, a shaft and an air inlet shutter mounted thereon having a projecting pin; of a tappet loosely mounted on said shaft, its mounted end being bifurcated to receive said pin and having a shoulder in normal engagement with said pin whereby said tappet acts to turn said shaft and open said shutter when swung in one direction, an arm hinged at its lower end to said door, a bolt pivotally secured to said arm and adapted to engage the front of the furnace when the door is closed, thereby to swing said arm outward when the door is closed, whereby its upper end engages and swings said tappet in shaft-turning direction, and then clears said tappet, gravity means for reversing the direction of the shaft after the arm clears the tappet, and a spring for reversing the movement of the arm when the door is opened, its upper end engaging and swinging the tappet out of engagement w1th said pro ect1ng pm and clearing sald tappet.

In testimony whereof I affix my signature.

JOHN J. A. MILLER. 

